Patent application title: MONITORING METHOD

Abstract:

Method for monitoring a body portion of a user during the use of a
gymnastic machine provided with a video monitoring apparatus; this method
comprising a phase of defining the body portion to be monitored, followed
by a phase of visually and continuously monitoring this body portion
through the video monitoring apparatus; this last phase comprising a
sub-phase of synchronizing the trend over time of the value of at least
one operating parameter of the video monitoring apparatus with a motion
of the body portion described on the basis of given kinematic information
acquired by a control unit of the gymnastic machine.

Claims:

1. Method for monitoring a body portion of a user during the use of a
given gymnastic machine provided with respective first programmable
electronic control means usable, in use, to acquire information related
to the method of performing the gymnastic exercises performed by said
user on said gymnastic machine; said method comprising a step of defining
said body portion to be monitored, followed by a step of visually and
continuously monitoring said body portion through video monitoring means;
said video monitoring means being designed to operate according to at
least a given respective operating parameter; said step of visually and
continuously monitoring said body portion comprising a step of acquiring
by said first electronic control means said kinematic information related
to the performance of the gymnastic exercises by said user; wherein said
step of visually and continuously monitoring said body portion further
comprises a step of synchronizing the evolution over time of the value of
at least a given operating parameter of said video monitoring means with
a motion of said body portion on the basis of said kinematic information
in order to perform, in real time, stable video tracking of said body
portion.

2. A method as claimed in claim 1, wherein said step of synchronizing the
evolution over time of the value of at least an operating parameter with
a motion of said body portion comprises the step of calculating, on the
basis of said kinematic information, at least a given first parameter of
a first kinematic function which describes the trajectory over time of
said body portion, followed by a step of varying over time at least a
given operating parameter according to a second mathematical function
comprising for each said first given parameter of said first kinematic
function a respective second given parameter of a value equivalent to the
corresponding said first given parameter.

3. A method as claimed in claim 2, wherein said first and second
functions are periodic and present a respective common frequency which is
substantially proportional to a performance speed and/or a performance
frequency of a respective gymnastic exercise on said gymnastic machine by
said user; at least one between said performance speed and/or performance
frequency being included in said kinetic information acquired by said
first control means of said gymnastic machine.

4. A method as claimed in claim 2, wherein said step of synchronizing the
evolution over time of the value of at least an operating parameter with
a motion of said body part comprises the step of automatically
calculating at least a third given parameter of said first kinematic
function which describes the trajectory over time of said body portion;
said step of automatically calculating at least a third given parameter
being performed through the application of an image recognition algorithm
with one or more frames filmed by said video monitoring means and related
to said user intent on performing respective physical exercises on said
gymnastic machine.

5. A method as claimed in claim 2, wherein each said first and/or second
function is periodic and substantially proportional to a given power of a
sine function or a cosine function.

6. A method as claimed in claim 4, wherein said video monitoring means
comprise at least a respective video filming device; each said first
and/or second function being periodic; at least a said third given
parameter of said first function alternatively comprising an amplitude or
an initial step of said first periodic function; said amplitude and said
initial phase which can be calculated through said known image
recognition algorithm starting from observation of an amplitude of
oscillation and of the initial position of said body portion inside a
visual field associated with said video filming device.

7. A method as claimed in claim 1, wherein said gymnastic machine
comprises at least an interface usable by said user for the performance
of respective gymnastic exercises and said first control means are
connected to a respective sensor device designed to continuously monitor
the position and/or the speed of displacement of at least a said
interface; said step of acquiring by said first electronic control means
kinematic information related to the performance of gymnastic exercises
performed by said user comprising the step of acquiring a performance
speed and/or a performance frequency of a respective gymnastic exercise
calculated by said first control means on the basis of the data output
from said sensor device.

8. A method as claimed in claim 1, wherein said video monitoring means
comprise at least a respective video filming device, suitable, in use, to
frame said body portion inside a frame portion of a respective visual
field; a said given operating parameter consisting in a position of said
frame portion inside said visual field.

9. A method as claimed in claim 8, wherein said step of visually and
continuously monitoring said body portion comprises a step of processing
the flow of video data output from said video filming device so that, in
said flow of video data, each single frame related to the entire visual
field is replaced by the respective portion related to the frame portion
in order to generate a video flow wherein said body portion is constantly
in a substantially central position of the frame.

10. A method as claimed in claim 1, wherein said video monitoring means
comprise at least a respective video filming device suitable, in use, to
frame said body portion inside a respective visual field; a said given
operating parameter comprising alternatively or in combination a position
and/or an angle of said video filming device.

11. A method as claimed in claim 8, wherein said step of defining said
body portion of said user to be monitored comprises a step of manually
selecting said frame portion of said visual field that frames said body
portion.

12. A method as claimed in claim 7, wherein said step of defining said
body portion of said user to be monitored comprises a step of
automatically identifying this said body portion through the application
of an image recognition algorithm to one or more frames associated with
the video data output from said video filming device.

13. A method as claimed in claim 1, wherein said step of defining said
body portion of said user to be monitored comprises a step of acquiring
given anthropometric data of said user by said first electronic control
means of said gymnastic machine.

14. A method as claimed in claim 6, wherein said gymnastic machine
comprises at least an interface usable by said user for the performance
of respective gymnastic exercises and said first control means are
connected to a respective sensor device designed to continuously monitor
the position and/or the speed of displacement of at least a said
interface; said step of acquiring by said first electronic control means
kinematic information related to the performance of gymnastic exercises
performed by said user comprising the step of acquiring a performance
speed and/or a performance frequency of a respective gymnastic exercise
calculated by said first control means on the basis of the data output
from said sensor device.

15. A method as claimed in claim 14, wherein said step of defining said
body portion of said user to be monitored comprises a step of
automatically identifying this said body portion through the application
of an image recognition algorithm to one or more frames associated with
the video data output from said video filming device; each said given
third parameter of said first function is updated at given time intervals
applying periodically said image recognition algorithm to the video data
output from said video filming device.

16. A method as claimed in claim 1, wherein said step of defining said
body portion to be monitored is preceded by a step of attracting the
attention of said user of said gymnastic machine through signalling means
of audio and/or video type.

17. A monitoring apparatus for a gymnastic machine, suitable, in use, to
continuously monitor a moving body portion of a user of said gymnastic
machine intent on performing physical exercises; said group comprising a
video filming device connected to first electronic control means designed
to regulate at least one operating parameter of said video filming
device; said first control means being arranged to acquire, in use, from
said second programmable control means of the gymnastic machine kinematic
information related to the performance of said physical exercises by said
user on said gymnastic machine; wherein said first control means are
arranged to synchronize, on the basis of said kinematic information, the
variation over time of the value of at least a said operating parameter
with a motion of said body portion, in order to perform, in real time,
stable and accurate tracking of said moving body portion.

18. An apparatus as claimed in claim 17, wherein said filming device
comprises, alternatively or in combination, a digital video-camera, a
webcam, an infrared sensor, or a known generic optoelectronic sensor.

19. An apparatus as claimed in Claim 17 comprising an actuator group
coupled with said video filming device and connected to said first
control means to allow, in use, fine real-time adjustments of the
position and/or orientation of said video filming device.

20. An apparatus as claimed in any one of claims 17, wherein said first
control means are programmed to acquire from said second means of said
gymnastic machine anthropometric data of said user to facilitate
operations for visual recognition and tracking of said body portion.

Description:

[0001] The present invention relates to a video monitoring method. More in
particular, the present invention relates to a video monitoring method
that can be used on a gymnastic machine provided with a respective video
monitoring apparatus. More in particular, the present invention relates
to a method for visually and continuously monitoring at least one moving
body portion of a user of a gymnastic machine during the execution of
respective physical exercises.

BACKGROUND TO THE INVENTION

[0002] Recently, in the field of fitness and sport practice performed
through gymnastic machines, the interest has been developed in providing
gymnastic machines with respective video filming apparatuses, for
visually and continuously monitoring a user during the execution of
respective gymnastic exercises. These video filming apparatuses are
usually constituted by an electro-optical filming device, for example a
digital camera or an infrared sensor, and by a respective programmable
control electronics allowing to set and adjust operating parameters of
video filming and giving, typically in digital format and in real time,
the flow of video data output from the filming device. The purpose of
providing gymnastic machines with respective video filming apparatuses is
that of visually and continuously monitoring at least one body portion,
for example the face, of the user during the execution of gymnastic
exercises. More in particular, the use of a digital camera or a webcam to
frame the face of a user of gymnastic machine can allow him/her to
perform live video-calls or videoconferences/video-chats during training.
This opportunity is particularly desirable during prolonged
cardiovascular training sessions, during which a user, in addition to
reading or listening to music, could be interested to communicate with
other people.

[0003] Alternatively, the opportunity of monitoring, during training, the
face or another body portion of a user of a gymnastic machine through
specific cameras or opto-electronic sensors, for example infrared
sensors, allows to acquire in real time biometric information about the
user, for example his/her heart rate.

[0004] However, it should be noted that, independently of the purpose of
the visually and continuously monitoring of a given body portion of a
user during training, the video monitoring apparatuses currently
available on the market, and their respective algorithms for tracking a
moving object, present limits that do not allow a satisfactory use
thereof in the sector of gymnastic machines. In fact, during a training
session with a gymnastic machine the face and the other body portions of
a user continuously move, and are therefore movable also inside the
visual field of the filming device or they can also exit it, thus making
literally impossible a continuous monitoring of the body portion. In this
regard, with reference to the common digital cameras available on the
market, it should be noted that algorithms are known for digital analysis
of the images, that allow to detect, and also to emphasise, the face of
the filmed subject; however these algorithms usually require at least
some tenths of a second to analyse a single image, and they cannot
therefore be used to analyse a film, i.e. a series of frames in rapid
succession, with a speed sufficient to track a face moving inside the
visual field of the films.

[0005] Consequently, by providing a gymnastic machine with a video
monitoring apparatus among those currently available on the market, it is
not possible to monitor continuously and in real time a face or another
body portion of a user, as the generally available control electronics of
the video filming device and the algorithms for analysing the images are
not suitable to track stably and in real time this body portion during
the execution of the training session. As a result, this instability in
tracking the body portion does not allow the body portion to be displayed
correctly in real time, and does not allow a correct evaluation of the
biometric parameters of the user during training.

[0006] In view of the situation described above, the problem of
performing, continuously and substantially in real time, a video
monitoring of a moving body portion of a user of a gymnastic machine
during a respective training session, is therefore currently unsolved. In
this regard, it would be desirable to have available a video monitoring
method that can be implemented through any video monitoring apparatus
associated with a gymnastic machine for visually and continuously
monitoring a body portion of a user of the gymnastic machine during the
execution of physical exercises. More in particular, it would be
desirable to have available a video monitoring method that allows
tracking, effectively and stably over time, a moving body portion so that
this latter is constantly framed substantially in the centre of the
visual field of the used monitoring apparatus.

SUMMARY OF THE INVENTION

[0007] The present invention relates to a monitoring method. More in
particular, the present invention relates to a video monitoring method.
More in particular, the present invention relates to a video monitoring
method that can be used on a gymnastic machine provided with a respective
video monitoring apparatus. More in particular, the present invention
relates to a method for continuously monitoring at least one body portion
of a user of a gymnastic machine during the execution of respective
physical exercises.

[0008] An object of the present invention is to provide a video monitoring
method that can be implemented through a video monitoring apparatus
connected to a gymnastic machine, and can be used to monitor continuously
a moving body portion of a user of this gymnastic machine during
execution of respective physical exercises. This monitoring method allows
the disadvantages described above to be solved and is therefore suitable
to satisfy a plurality of requirements that to date have still not been
addressed, and therefore suitable to represent a new and original source
of economic interest, capable of modifying the current market of fitness
equipment and, more in general, of gymnastic machines.

[0009] According to the present invention a method is provided for video
monitoring a moving body portion of a user of a gymnastic machine, and
the main characteristics of this method will be described in at least one
of the appended claims.

[0010] A further object of the present invention is to provide a video
monitoring apparatus designed to be used in combination with a gymnastic
machine for visually and continuously monitoring a body portion of a user
of this gymnastic machine.

[0011] According to the present invention, a monitoring apparatus is
provided, whose main characteristics will be described in at least one of
the appended claims.

[0012] A further object of the present invention is to describe a use of a
video monitoring apparatus in combination with a gymnastic machine for
visually and continuously monitoring at least one body portion of a user
of this gymnastic machine.

[0013] According to the present invention, a use is illustrated for a
video monitoring apparatus: the main characteristics of this use will be
described in at least one of the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

[0014] Further characteristics of the video monitoring apparatus and of
the respective monitoring method according to the present invention will
be more apparent from the description below, set forth with reference to
the accompanying drawings, which illustrate some non-limiting examples of
embodiment, in which identical or corresponding parts of the apparatus
are identified by the same reference numbers. In particular:

[0015]FIG. 1 is a perspective schematic view of a gymnastic machine
provided with a video monitoring apparatus according to the present
invention;

[0016] FIG. 2 illustrates a detail extracted from FIG. 1 and represented
in enlarged scale and according to a plurality of preferred embodiments;
and

[0017] FIG. 3 illustrates a flow diagram relating to a preferred
embodiment of the video monitoring method according to the present
invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0018] In FIG. 1 number 1 indicates, in its entirety, a video monitoring
apparatus connected to a gymnastic machine 100 and designed to film a
user during training on this gymnastic machine 100. In particular, the
video monitoring apparatus 1 comprises at least one opto-electronic video
filming device 10, preferably of the digital type, suitable, in use, to
film at least one body portion of a user in training on the gymnastic
machine 100. In more detail, this video filming device 10 comprises
preferably, although without limitation, a digital camera 10 or a webcam
10 designed to supply, substantially in real time, a continuous flow of
video data output about what has been filmed. The video filming device 10
can alternatively comprise an infrared sensor or any other type of
opto-electronic sensor of the known type suitable, in use, to supply,
substantially in real time, a flow of video data output; preferably of
the digital type, representing what has been filmed by this video filming
device 10.

[0019] At this point, with particular reference to FIGS. 2a and 2b, it
should be noted that the video filming device 10 can be of the fixed type
and present a respective visual field CV dimensioned so as to frame a
part of the user's body of significant dimensions and, anyway, of
dimensions greater than the given body portion that one desires to
monitor during training. In this way, even if this body portion to be
monitored will move during the use of the gymnastic machine 10, the
filming device 10 should be however able to frame it inside its visual
field CV. Alternatively, as illustrated in FIG. 2B, the video monitoring
apparatus 1 can comprise an actuator group 11, provided with one or more
actuators of the known type, that is coupled to the video filming device
10 to move and direct it so that, in use, the body portion to be
monitored, even if moving, is maintained constantly in a substantially
central position of the visual field of the video filming device 10. Just
by way of example, it could be advisable to note that, to direct a video
filming device 10 of small dimensions, for example a simple
opto-electronic sensor presenting a surface of maximum a pair of
cm2, it will be possible to use actuators of the type generally used
in the CD and DVD players to direct the laser read head.

[0020] It should be noted that the video monitoring apparatus 1, and in
particular the filming device 10, is preferably dimensioned and shaped so
that it can be integrated into the structure of the gymnastic machine
100, for example, as illustrated in FIGS. 2a and 2b, inside a console for
controlling and adjusting the operating parameters of the gymnastic
machine 100. Alternatively, at least the video filming device 10 can be
supported by a wall or by a respective upright so that the intensity of
the vibrations, transmitted by the user to the video monitoring apparatus
1 through the frame of the gymnastic machine 100, is minimised.

[0021] The video monitoring apparatus 1 further comprises a respective
electronic first control unit 20 connected to each video filming device
10 and, as it will be better described hereunder, suitable, in use, both
to adjust given operating parameters P of each video filming device 10
and to process electronically the video signal output from the devices
10. This first control unit 20 can be of the known type, for example,
although without limitation, a micro PC.

[0022] With reference to FIG. 2, it should be noted that the first control
unit 20 associated with the video monitoring apparatus 1 is connected to
a programmable second control unit 120 associated with the gymnastic
machine 100. This second control unit 120 is designed so as to allow the
user to set operating parameters of the gymnastic machine 100 to define
the characteristics of the exercises he/she wants to perform. Moreover,
through a respective fist interface 122, for example a keyboard or a
touchpad, the user can give the second control unit 120 the value of some
of his/her anthropometric characteristics, for example his/her weight or
height, that will be preferably stored in a memory associated with the
second control unit 120 and can be used to personalise the exercises that
can be performed through the gymnastic machine 100.

[0023] Lastly it should be noted that, even if not illustrated in the
figures, the first and the second electronic control unit 20 and 120
could match each other, and they could be therefore produced through a
single programmable computing unit that, in use, will be responsible for
managing both the operating training parameters of the gymnastic machine
100 and operating parameters P of the video monitoring apparatus 1, and,
in case, the digital processing of the video data output from the video
filming device 10. Again with reference to the second control unit 120,
it should be noted that this latter can be preferably connected to at
least one respective sensor 121 suitable, in use, to monitor continuously
kinematic characteristics of the motion of a second interface 101
designed to allow each user to interact with the machine 100 and with a
respective load group, if any, known and therefore not illustrated. For
example, with reference to FIG. 1 the illustrated gymnastic machine 100
is an endless belt 100 or a treadmill provided with an endless belt that
is carried by at least one pair of rollers and can be interpreted as a
second interface 101 for the user of the gymnastic machine 100. In this
case, the second control unit 120 can be connected to at least one
respective sensor 121, for example a magnetic transducer, designed to
provide, in real time, the value of the instantaneous speed of movement
of the belt or, in an equivalent manner, the value of the instantaneous
speed of rotation of the rollers supporting the belt. Alternatively, a
sensor 121 can comprise a pressure sensor designed to measure the
evolution over time of the pressure exerted by the feet of the user on
the belt and, consequently, to allow the second control unit 120 to
calculate, substantially in real time, a frequency ω of the step of
this user.

[0024] At this point, before proceeding with a detailed description of the
video monitoring method that can be actuated through the video monitoring
apparatus 1 describe above, it should be noted that the choice of
representing, in FIGS. 1 and 2, the gymnastic machine 100 as an endless
belt 100 provided with a camera 10 has been made just by way of example,
and it does not limit the scope of use and of protection of the video
monitoring apparatus 1 according to the present invention and of the
respective video monitoring method that, contrarily, can be used with
gymnastic machines of any type. However, to simplify the description of
the video monitoring method according to the present invention,
hereinafter reference will be made exclusively to a gymnastic machine 100
constituted by an endless belt 100, such as that illustrated in FIGS. 1
and 2, provided with at least one camera 10. Furthermore, again to
simplify the description of the method according to the present
invention, and just by way of non-limiting example, reference will be
made to a single body portion to be monitored, constituted by the face of
the user performing running exercises on the endless belt 100.

[0025] At this point, before detailing the phases composing the method, it
should be specified that hereinafter the term video monitoring method
means a video filming method for filming a given subject, in particular a
body portion of the user, this method, implemented on a video monitoring
apparatus, allowing to obtain, in real time, a flow of video data, for
example a film, wherein the given subject is maintained stably in a
respective given framing position, for example in a substantially central
portion of the visual field CV associated to the video filming device 10.
In this way, the flow of data output from the video monitoring apparatus
1 can be used in any video application requiring that the filmed subject
is maintained stably in a respective framing position, for example the
application of algorithms of image analysis aimed at evaluating, in real
time, biometric characteristics of the monitored subject.

[0026] First of all, the video monitoring method according to the present
invention comprises a phase of defining the user's body portion, in this
case the face, that one desires to monitor visually and continuously.
This phase of defining the body portion can comprise a phase of manually
selecting a framing portion PCV of the visual field CV of the video
filming device 10, framing the body portion in question, the face in this
case, in a time instant preferably immediately preceding the start of the
training session on the machine 100. Alternatively, the phase of defining
the body portion to be monitored can comprise a phase of automatically
identifying this body portion by applying an image recognition algorithm
to the video data output from the video filming device 10. Anyway, this
phase of automatically identifying the body portion to be monitored will
be performed in a time instant preceding the start of the training
session on the machine 100, so as to allow the image recognition
algorithm to work on one or more frames of a video flow wherein the
user's face is substantially immovable over time and therefore easy to be
recognised. This algorithm can be performed preferably, although without
limitation, by the first electronic control unit 20 that comprises a
respective known calculating group and receives from the video filming
device 10 a flow of raw video data, i.e. data not processed and relating
to all the visual field CV. It should be noted that, to facilitate this
phase of automatically identifying the body portion to be monitored, the
gymnastic machine 100 can be provided with an audio and/or video
signalling element 123, for example a LED or an electronic buzzer,
designed to attract the user's attention towards a front console of the
gymnastic machine, so that the user tends to rotate his/her face towards
the camera 10. Consequently, the monitoring method according to the
present invention can comprise a phase of attracting the attention of the
user of the gymnastic machine 100 through a signalling element 123 of the
audio and/or video type, preceding the phase of defining the body portion
to be monitored.

[0027] At this point, once the phase of defining the body portion to be
monitored has been finished, the gymnastic training can start and the
body portion in question will start to move according to schemes typical
of the training method performed through the gymnastic machine 100. For
example, with reference to an endless belt 100, the user's face, when
observed frontally from the point of view of the camera 10, will start to
move inside the visual field CV with a substantially periodic vertical
motion between an upper end YMAX and a lower end YMIN. This
motion can be kinematically approximated with a simple harmonic motion,
or, in other words, with a motion described by a periodic circular
function, for example a sinusoidal or cosinusoid function or,
alternatively, a function equivalent to an integer power of a sine or
cosine. For example, hereinafter a first sinusoidal function F1 will be
used to describe the motion of the user's face inside the visual field CV
associated with the camera 10. This function can be written in the form
F1(t)=Yface(t)=Asin(2πνt+φ0) where:

Yface is the position of the face in the visual field CV; A is the
amplitude of oscillation of the face in the visual field CV, equivalent
to YMAX-YMIN; ν is the oscillation frequency of the user's
face; φ0 is the starting phase of the oscillation.

[0028] Consequently, knowing these parameters A, ν and φ0 it
is possible to know, in every time instant t, the position of the user's
face inside the visual field CV and therefore to foresee how this face
will move whilst the user executes a running training session. It is
therefore clearly apparent that, synchronising a given operating
parameter P associated to the operations of video filming performed
through the video monitoring apparatus 1 with the assumed values of the
first function F1, and therefore with the real motion of the user's face
relative to the frame of the gymnastic machine 100, it will be possible
to monitor stably over time the user's face, and therefore provide a flow
of video data wherein it is possible to detect, in each respective frame,
the user's face, substantially in real time.

[0029] For instance, by knowing a priori the position of the face in the
instant t, thanks to the first sinusoidal function F1, it will be
possible to direct the video filming device 10 through a respective
actuator group 11 so that it frames the user's face constantly in the
centre of its visual field CV. Alternatively, if one desires to use a
fixed video filming device 10, knowing the first function F1 will allow
to move the framing portion PCV of the visual field CV so that it frames
constantly in its centre the user's face. At this point, during
processing in real time the raw signal output from the video filming
device 10, it will be sufficient to "cut" or emphasise digitally in each
frame the framing portion PCV of the visual field CV to obtain a video
data flow wherein the user's face is stably in a substantially central
position of each frame. In this regard, it should be noted that both the
solution of physically directing the video filming device 10 and the
solution of varying the position on the framing portion PCV inside the
respective visual field CV, in a manner substantially synchronous with
the movements of the user's face, can be interpreted as operations of
tracking the user's body portion one desires to monitor visually
substantially in real time.

[0030] At this point, in view of the above description with reference to
the video monitoring method according to the present invention, it should
be specified that, once the phase of defining the body portion to be
monitored has been ended, a phase occurs of acquiring from the second
control unit 120 of the gymnastic machine 100 information of kinematic
nature related to the gymnastic exercise performed at that moment by the
user. This information of kinematic nature can comprise, for example,
although without limitation, a speed V or a frequency ω of
execution of the gymnastic exercise by the user. Starting from these
data, the first control group 20, or any other calculating unit
associated with the video monitoring apparatus 1, can perform the phase
of calculating the frequency ν of the first function F1 hat generally
matches an integer multiple of the frequency ω or of the speed V of
execution of the gymnastic exercise performed by the user of the
gymnastic machine 100.

[0031] The monitoring method according to the present invention further
comprises a phase of automatically calculating at least one parameter of
the first function F1 starting from the processing of the flow of raw
video data output from the video filming device 10. This phase can be
performed using known image processing algorithms than can be used also
to perform the previous phase of automatically identifying the body
portion to be monitored. These known algorithms, even if not usable to
analyse in real time a video data flow, can be used however to analyse a
reduced number of frames in succession or near in the time, in order to
identify some kinematic characteristics of the movement of the user's
face, for instance a respective initial position Y0 when starting
the gymnastic exercise and the end positions YMIN and YMAX.
Starting from these kinematic data obtained by analysing raw video data,
the first control unit 20 can perform the phase of calculating further
parameters of the first function F1, for example the initial phase
φ0 that can be calculated through the inverse function of the
sin applied to the initial position Y0 of the user's face in the
visual field CV, or the amplitude A given by the difference between the
end positions YMAX and Ymin of the oscillating motion of the user's
face.

[0032] At this point, the method according to the present invention
comprises a phase of calculating, preferably through the use of the first
control unit 20, the first function F1 based upon both the data obtained
from the observation of the user's face and the kinematic information
given by the second control unit 120 of the gymnastic machine 100. The
method for monitoring the user's face further comprises a phase of
varying over time the value of at least one given operating parameter P
of the video monitoring apparatus 1 according to a respective second
periodic function F2 presenting substantially the same frequency ν as
the first function F1. Each of these second functions F2 is associated
with a respective given operating parameters P associated with the video
monitoring apparatus 1 and is calculated starting from the first function
F1 associated with the movement of the user's face, so that the variation
over time of each of these given operating parameters P of the video
monitoring apparatus 1 is substantially synchronous with the oscillating
movement of the user's face. Therefore, this phase of varying over time
the value of at least one given operating parameter P of the video
monitoring apparatus 1 according to a respective second periodic function
F2 can be interpreted as a phase of synchronising the trend over time of
the value of at least one given operating parameter P of the video
monitoring apparatus 1 with the movement of the body portion calculated
based upon the information of kinematic nature acquired by the second
control unit 120 of the gymnastic machine.

[0033] At this point it should be noted that these given operating
parameters associated with the video monitoring apparatus 1 can comprise
for example a position and/or an angle of the video filming device 10 so
that the direction of this device 10 varies in real time in a synchronous
manner with the oscillation of the user's face that, consequently, will
be maintained stably in the centre of the visual field of the video
filming device 10. In combination with, or alternatively to, what
illustrated above, these given operating parameters P of the video
monitoring apparatus 1 can comprise a position of the framing portion
inside the respective visual field CV. In this way, moving the framing
portion with an oscillating motion synchronous with the motion of the
user's face, this body portion will be maintained stably in the centre of
the framing portion PCV.

[0034] In any case, independently of the operating parameters P that one
desires to vary synchronously with the oscillation of the user's face, it
should be noted that the set of the phases of calculating the parameters
of the first kinematic function F1, of the phase of calculating the
second mathematic function F2 on the basis of at least one parameter of
the first function F1, and the phase of synchronising the trend over time
of the value of at least one given operating parameter P of the video
monitoring apparatus 1 with the second mathematic function F1, and
therefore with the motion of the body portion, can be interpreted as a
method for tracking a moving body portion of a user of the gymnastic
machine 100 during execution of the respective physical exercises.

[0035] At this point it should be noted that, if the solution has been
chosen of varying the position of the framing portion PCV inside the
visual field CV synchronously with the user's face, the monitoring method
according to the present invention can comprise a phase of processing the
flow of video data output from the device 10, aimed at extracting from
each frame only the data related to the framing portion PVC of the visual
field CV, so that the flow of video data resulting from this processing
is a film substantially composed by frames corresponding to what framed
inside the framing portion PCV.

[0036] Therefore, in view of the above description, it is clearly apparent
that the video monitoring apparatus 1 connected with the gymnastic
machine 100 and the respective video monitoring method according to the
present invention allow the technical problem in question to be solved,
and therefore allow to monitor substantially in real time and in a stable
and continuous manner a moving body portion of a user of the gymnastic
machine 100 during execution of the respective physical exercises. In
this regard it should be noted that, even if there are algorithms for
tracking moving objects known and that can be applied to video monitoring
systems available on the market, however these tracking algorithms are
usually unable to monitor in real time the movement of a body portion of
a moving sportsman, as, based upon a real time analysis of the video
filming of the motion of the body portion, the evaluation of all the
kinematic characteristics of this motion necessary to obtain a correct
tracking by the monitoring system is difficult, and characterised by a
high degree of approximation. Vice versa, the monitoring method performed
according to the present invention comprises a phase of tracking the body
portion that is based not only upon a visual evaluation of some kinematic
variables of the motion of the subject to be monitored, but above all on
the acquisition by the control unit of the gymnastic machine 100 of
kinematic data on the gymnastic exercises performed at that moment by the
user. The use of these kinematic data allows to obtain a reliable and
accurate tacking, as based upon these kinematic data acquired
independently of an analysis of a flow of video data collected by the
video filming device 10, and are characterised by a high accuracy, and
obtained as a result of a substantially direct measurement by the second
control unit 120 and at least one respective sensor 121.